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%I #7 Jul 03 2013 09:24:23
%S 1,4,9,11,14,18,21,23,24,31,32,33,34,37,40,41,44,46,49,51,54,55,60,61,
%T 62,64,65,66,71,74,75,77,79,81,84,88,89,91,92,93,94,99,100,101,102,
%U 104,106,107,111,113,114,116,118,121,123,124,127,128,130,131,134,135,138,141,143,144,149,150,151,153,154,157,158,161,163,164,165,168,169,170
%N Numbers n such that 3n+6, 3n+7 and 3n+8 are all composite.
%D Ernest V. Miliauskas, letter to _N. J. A. Sloane_, Dec 21 1985.
%F a(n) = A199593(n)-8.
%o (PARI) is(n)=!isprime(bitor(3*n+7,1)) \\ _Charles R Greathouse IV_, Jul 03 2013
%K nonn,easy
%O 1,2
%A _N. J. A. Sloane_, Nov 08 2011
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